This Camera Calculator finds the Lens Focal Length From the Target Field of View

Camera Lens Effective Focal Length Calculator

A Camera Focal Length Calculator. This Calculates a Lens EFL for Cameras.
A Camera Focal Length Calculator. This Calculates a Lens EFL for Cameras.

This effective focal length calculator helps you select a lens to use with your camera. The calculator takes your target field of view (angle of view) and camera specification then provides the required lens EFL.

The calculator uses the camera lens focal length equation. This formula is different than the lens maker's equation which is intended for simple thin lens elements.

The Optical Effective Focal Length (EFL) should not be confused with the Mechanical Back-Focal Length (BFL). The EFL determines the field of view of the camera while the BFL determines whether a lens will focus on a camera.

Read Our Camera Calculator & Optics Design Page, or Click below Use our Other Camera Calculators

Camera Field of View Calculator. FoV Calculator
Camera Depth of Field Calculator. DoF Calculator.
Camera Angle of View Calculator for Camera Lens Selection. AoV Calculator.

Here are a Few M12 Lenses. Search all 50+ Using Our M12 Lens Calculator

Telephoto 16mm M12 Lens

CIL160-F1.9-M12A650

Telephoto 16mm M12 Lens

Telephoto 35mm M12 Lens

CIL350-F2.4-M12A650

Telephoto 35mm M12 Lens

Low Distortion 3.0mm M12 Lens

CIL030-F2.1-M12A650

Low Distortion 3.0mm M12 Lens

Low Distortion 2.7mm M12 Lens

CIL027-F2.8-M12A650

Low Distortion 2.7mm M12 Lens

Large Format 3.5mm M12 Lens

CIL334-F2.2-M12C660

Large Format 3.5mm M12 Lens

We Also have Cost Effective 12MP+ C-Mount Lenses for Machine Vision and Factory Automation.

IMX226 Dart Camera 3mm M12 Lens
IMX226 Dart Camera 3mm M12 Lens
Mipi camera M12 Lens for S-Mount FLIR
Arducam IMX477 2.7mm M12 Lens
CIL027-F2.8-M12A650
Low Distortion 2.7mm M12 Lens
$39.00
3.5mm M12 Lens for IMX226 AR0821 IMX537
3.5mm M12 Lens for IMX226 AR0821 IMX537
S-Mount Drone Lens for Wide Angle IMX226
Wide Angle Drone Lens for IMX226
CIL334-F2.2-M12C660
Large Format 3.5mm M12 Lens
$29.00
7mm M12 Lens GMSL Camera
7mm M12 Lens GMSL Camera
7mm M12 Lenses USB3 FLIR
Basler Dart Camera 7mm SMount Lens
CIL068-F2.5-M12A650
Low Distortion 6.8mm M12 Lens
$59.00
Fisheye Lens for 1/2.3
Fisheye Lens for 1/2.3
M12 Fisheye Lens for 20MP cameras
195 degree S Mount Lens for AR1820HS
CIL216-F2.2-M12A650
195°@4.7mm Fisheye M12 Lens
$59.00
Wide Angle Fisheye Lens for S Mount. Entaniya Raspberry Pi RP-L100
Wide Angle Fisheye Lens for S Mount. Entaniya Raspberry Pi RP-L100
Fisheye Wide Angle M12 Lens Entaniya RP-L100 DesignSpark
Board Mount Lens Wide Angle Fisheye Entaniya RP-L100
CIL227-F2.5-M12B660
185°@7.8mm Fisheye M12 Lens
$29.00
Mini Fisheye S Mount Lens
Mini Fisheye S Mount Lens
Tiny Fisheye Lens
Miniature Fisheye
CIL217-F2.7-M12A650
200°@5.7mm IP67 Fisheye M12 Lens
$39.00

What's Your Application? Our Lenses Cover the Spectrum.

190°@9.1mm Fisheye M12 Lens

CIL231-F1.9-M12A650

190°@9.1mm Fisheye M12 Lens

Wide-Angle 2.7mm M12 Lens

CIL327-F1.5-M12A660

Wide-Angle 2.7mm M12 Lens

200°@7.2mm Fisheye M12 Lens

CIL324-F1.9-M12ANIR

200°@7.2mm Fisheye M12 Lens

Mobile Robotics?

Find a low F# or low distortion lens to optimize your computer vision.

Factory Machine Vision?

Our cost-effective compact C-Mount lenses are designed for up to 1.1"~1.2" format global shutter sensors.

200°@2.9mm Fisheye M12 Lens

CIL208-F2.2-M12A650

200°@2.9mm Fisheye M12 Lens

Low Distortion 6mm M12 Lens

CIL060-F2.8-M12A650

Low Distortion 6mm M12 Lens

Low Distortion 3.0mm M12 Lens

CIL030-F2.1-M12A650

Low Distortion 3.0mm M12 Lens

Intelligent Everywhere?

Our low distortion lenses with multiple F# can be used to optimize your depth of field.

Surveillance?

Our fisheye and IR Corrected lenses are suitable for doorbell cameras and active IR illuminated scenes.

Telephoto 12mm M12 Lens

CIL125-F2.4-M12NIR

Telephoto 12mm M12 Lens

Low Distortion 2.2mm M12 Lens

CIL023-F2.2-M12A650

Low Distortion 2.2mm M12 Lens

Wide-Angle 4.4mm M12 Lens

CIL344-F1.9-M12B660

Wide-Angle 4.4mm M12 Lens

Wide-Angle 4.4mm M12 Lens

CIL343-F2.3-M12ANIR

Wide-Angle 4.4mm M12 Lens

Wide-Angle 5.8mm M12 Lens

CIL358-F1.9-M12A650

Wide-Angle 5.8mm M12 Lens

Wide-Angle 6.8mm M12 Lens

CIL368-F1.8-M12A650

Wide-Angle 6.8mm M12 Lens

Does it Require Getting Dirty?

Our IP67 and IP69K lenses are suitable for applications exposed to the environment.

Aerial Robotics?

Our tiny lenses are ideal for collision avoidance and object recognition.

Telephoto 26mm M12 Lens

CIL260-F2.0-M12IR

Telephoto 26mm M12 Lens

188°@6.6mm IP67 M12 Fisheye

CIL222-F2.0-M12A650

188°@6.6mm IP67 M12 Fisheye

215°@6.8mm M12 Fisheye Lens

CIL220-F2.3-M12B650

215°@6.8mm M12 Fisheye Lens